[游戏开发]瞎写的游戏

import pygame,sys
from pygame.locals import *
pygame.init()
width=650
height=650
screen=pygame.display.set_mode((width,height))
pygame.display.set_caption('my game')
fly = pygame.image.load("./img/fly.png")
fly_rect = fly.get_rect()
distance = [0, 0]
fps = 100
fclock =pygame.time.Clock()
while True: # 游戏循环
    for event in pygame.event.get():
        if event.type == QUIT:
            pygame.quit()
            sys.exit()
    pressed_keys = pygame.key.get_pressed()
    if pressed_keys[pygame.K_d]:
        distance[0] += .1
    elif pressed_keys[pygame.K_a]:
        distance[0] -= .1
    elif pressed_keys[pygame.K_w]:
        distance[1] -= .1
    elif pressed_keys[pygame.K_s]:
        distance[1] += .1
    else:distance=[0, 0]
    if fly_rect.left < 0:
        if distance[0] < 0 :distance[0]=0
    elif   fly_rect.right > width:
        if distance[0]>0:distance[0]=0
    elif fly_rect.top < 0 :
        if distance[1]<0:distance[1]=0
    elif fly_rect.bottom > height:
        if distance[1]>0:distance[1]=0
    fly_rect = fly_rect.move(distance[0], distance[1])
    #screen.fill((0,0,0))
    screen.blit(fly, fly_rect)
    pygame.display.update()
    fclock.tick(fps)

运行后如图，方块可操控上下左右移动（通过wasd）?

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